diff options
Diffstat (limited to 'test/iptables')
| -rw-r--r-- | test/iptables/BUILD | 31 | ||||
| -rw-r--r-- | test/iptables/README.md | 44 | ||||
| -rw-r--r-- | test/iptables/filter_input.go | 124 | ||||
| -rw-r--r-- | test/iptables/iptables.go | 53 | ||||
| -rw-r--r-- | test/iptables/iptables_test.go | 179 | ||||
| -rw-r--r-- | test/iptables/iptables_util.go | 82 | ||||
| -rw-r--r-- | test/iptables/runner/BUILD | 16 | ||||
| -rw-r--r-- | test/iptables/runner/Dockerfile | 4 | ||||
| -rw-r--r-- | test/iptables/runner/main.go | 70 |
9 files changed, 603 insertions, 0 deletions
diff --git a/test/iptables/BUILD b/test/iptables/BUILD new file mode 100644 index 000000000..fa833c3b2 --- /dev/null +++ b/test/iptables/BUILD @@ -0,0 +1,31 @@ +load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test") + +package(licenses = ["notice"]) + +go_library( + name = "iptables", + srcs = [ + "filter_input.go", + "iptables.go", + "iptables_util.go", + ], + importpath = "gvisor.dev/gvisor/test/iptables", + visibility = ["//test/iptables:__subpackages__"], +) + +go_test( + name = "iptables_test", + srcs = [ + "iptables_test.go", + ], + embed = [":iptables"], + tags = [ + "local", + "manual", + ], + deps = [ + "//pkg/log", + "//runsc/dockerutil", + "//runsc/testutil", + ], +) diff --git a/test/iptables/README.md b/test/iptables/README.md new file mode 100644 index 000000000..b37cb2a96 --- /dev/null +++ b/test/iptables/README.md @@ -0,0 +1,44 @@ +# iptables Tests + +iptables tests are run via `scripts/iptables\_test.sh`. + +## Test Structure + +Each test implements `TestCase`, providing (1) a function to run inside the +container and (2) a function to run locally. Those processes are given each +others' IP addresses. The test succeeds when both functions succeed. + +The function inside the container (`ContainerAction`) typically sets some +iptables rules and then tries to send or receive packets. The local function +(`LocalAction`) will typically just send or receive packets. + +### Adding Tests + +1) Add your test to the `iptables` package. + +2) Register the test in an `init` function via `RegisterTestCase` (see +`filter_input.go` as an example). + +3) Add it to `iptables_test.go` (see the other tests in that file). + +Your test is now runnable with bazel! + +## Run individual tests + +Build the testing Docker container: + +```bash +$ bazel run //test/iptables/runner -- --norun +``` + +Run an individual test via: + +```bash +$ bazel test //test/iptables:iptables_test --test_filter=<TESTNAME> +``` + +To run an individual test with `runc`: + +```bash +$ bazel test //test/iptables:iptables_test --test_filter=<TESTNAME> --test_arg=--runtime=runc +``` diff --git a/test/iptables/filter_input.go b/test/iptables/filter_input.go new file mode 100644 index 000000000..923f44e68 --- /dev/null +++ b/test/iptables/filter_input.go @@ -0,0 +1,124 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package iptables + +import ( + "fmt" + "net" + "time" +) + +const ( + dropPort = 2401 + acceptPort = 2402 + sendloopDuration = 2 * time.Second + network = "udp4" +) + +func init() { + RegisterTestCase(FilterInputDropUDP{}) + RegisterTestCase(FilterInputDropUDPPort{}) + RegisterTestCase(FilterInputDropDifferentUDPPort{}) +} + +// FilterInputDropUDP tests that we can drop UDP traffic. +type FilterInputDropUDP struct{} + +// Name implements TestCase.Name. +func (FilterInputDropUDP) Name() string { + return "FilterInputDropUDP" +} + +// ContainerAction implements TestCase.ContainerAction. +func (FilterInputDropUDP) ContainerAction(ip net.IP) error { + if err := filterTable("-A", "INPUT", "-p", "udp", "-j", "DROP"); err != nil { + return err + } + + // Listen for UDP packets on dropPort. + if err := listenUDP(dropPort, sendloopDuration); err == nil { + return fmt.Errorf("packets on port %d should have been dropped, but got a packet", dropPort) + } else if netErr, ok := err.(net.Error); !ok || !netErr.Timeout() { + return fmt.Errorf("error reading: %v", err) + } + + // At this point we know that reading timed out and never received a + // packet. + return nil +} + +// LocalAction implements TestCase.LocalAction. +func (FilterInputDropUDP) LocalAction(ip net.IP) error { + return sendUDPLoop(ip, dropPort, sendloopDuration) +} + +// FilterInputDropUDPPort tests that we can drop UDP traffic by port. +type FilterInputDropUDPPort struct{} + +// Name implements TestCase.Name. +func (FilterInputDropUDPPort) Name() string { + return "FilterInputDropUDPPort" +} + +// ContainerAction implements TestCase.ContainerAction. +func (FilterInputDropUDPPort) ContainerAction(ip net.IP) error { + if err := filterTable("-A", "INPUT", "-p", "udp", "-m", "udp", "--destination-port", fmt.Sprintf("%d", dropPort), "-j", "DROP"); err != nil { + return err + } + + // Listen for UDP packets on dropPort. + if err := listenUDP(dropPort, sendloopDuration); err == nil { + return fmt.Errorf("packets on port %d should have been dropped, but got a packet", dropPort) + } else if netErr, ok := err.(net.Error); !ok || !netErr.Timeout() { + return fmt.Errorf("error reading: %v", err) + } + + // At this point we know that reading timed out and never received a + // packet. + return nil +} + +// LocalAction implements TestCase.LocalAction. +func (FilterInputDropUDPPort) LocalAction(ip net.IP) error { + return sendUDPLoop(ip, dropPort, sendloopDuration) +} + +// FilterInputDropDifferentUDPPort tests that dropping traffic for a single UDP port +// doesn't drop packets on other ports. +type FilterInputDropDifferentUDPPort struct{} + +// Name implements TestCase.Name. +func (FilterInputDropDifferentUDPPort) Name() string { + return "FilterInputDropDifferentUDPPort" +} + +// ContainerAction implements TestCase.ContainerAction. +func (FilterInputDropDifferentUDPPort) ContainerAction(ip net.IP) error { + if err := filterTable("-A", "INPUT", "-p", "udp", "-m", "udp", "--destination-port", fmt.Sprintf("%d", dropPort), "-j", "DROP"); err != nil { + return err + } + + // Listen for UDP packets on another port. + if err := listenUDP(acceptPort, sendloopDuration); err != nil { + return fmt.Errorf("packets on port %d should be allowed, but encountered an error: %v", acceptPort, err) + } + + return nil +} + +// LocalAction implements TestCase.LocalAction. +func (FilterInputDropDifferentUDPPort) LocalAction(ip net.IP) error { + return sendUDPLoop(ip, acceptPort, sendloopDuration) +} diff --git a/test/iptables/iptables.go b/test/iptables/iptables.go new file mode 100644 index 000000000..2e565d988 --- /dev/null +++ b/test/iptables/iptables.go @@ -0,0 +1,53 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package iptables contains a set of iptables tests implemented as TestCases +package iptables + +import ( + "fmt" + "net" +) + +// IPExchangePort is the port the container listens on to receive the IP +// address of the local process. +const IPExchangePort = 2349 + +// A TestCase contains one action to run in the container and one to run +// locally. The actions run concurrently and each must succeed for the test +// pass. +type TestCase interface { + // Name returns the name of the test. + Name() string + + // ContainerAction runs inside the container. It receives the IP of the + // local process. + ContainerAction(ip net.IP) error + + // LocalAction runs locally. It receives the IP of the container. + LocalAction(ip net.IP) error +} + +// Tests maps test names to TestCase. +// +// New TestCases are added by calling RegisterTestCase in an init function. +var Tests = map[string]TestCase{} + +// RegisterTestCase registers tc so it can be run. +func RegisterTestCase(tc TestCase) { + if _, ok := Tests[tc.Name()]; ok { + panic(fmt.Sprintf("TestCase %s already registered.", tc.Name())) + } + Tests[tc.Name()] = tc +} diff --git a/test/iptables/iptables_test.go b/test/iptables/iptables_test.go new file mode 100644 index 000000000..bfbf1bb87 --- /dev/null +++ b/test/iptables/iptables_test.go @@ -0,0 +1,179 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package iptables + +import ( + "fmt" + "net" + "os" + "path" + "testing" + "time" + + "flag" + "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/runsc/dockerutil" + "gvisor.dev/gvisor/runsc/testutil" +) + +const timeout time.Duration = 10 * time.Second + +var image = flag.String("image", "bazel/test/iptables/runner:runner", "image to run tests in") + +type result struct { + output string + err error +} + +// singleTest runs a TestCase. Each test follows a pattern: +// - Create a container. +// - Get the container's IP. +// - Send the container our IP. +// - Start a new goroutine running the local action of the test. +// - Wait for both the container and local actions to finish. +// +// Container output is logged to $TEST_UNDECLARED_OUTPUTS_DIR if it exists, or +// to stderr. +func singleTest(test TestCase) error { + if _, ok := Tests[test.Name()]; !ok { + return fmt.Errorf("no test found with name %q. Has it been registered?", test.Name()) + } + + // Create and start the container. + cont := dockerutil.MakeDocker("gvisor-iptables") + defer cont.CleanUp() + resultChan := make(chan *result) + go func() { + output, err := cont.RunFg("--cap-add=NET_ADMIN", *image, "-name", test.Name()) + logContainer(output, err) + resultChan <- &result{output, err} + }() + + // Get the container IP. + ip, err := getIP(cont) + if err != nil { + return fmt.Errorf("failed to get container IP: %v", err) + } + + // Give the container our IP. + if err := sendIP(ip); err != nil { + return fmt.Errorf("failed to send IP to container: %v", err) + } + + // Run our side of the test. + errChan := make(chan error) + go func() { + errChan <- test.LocalAction(ip) + }() + + // Wait for both the container and local tests to finish. + var res *result + to := time.After(timeout) + for localDone := false; res == nil || !localDone; { + select { + case res = <-resultChan: + log.Infof("Container finished.") + case err, localDone = <-errChan: + log.Infof("Local finished.") + if err != nil { + return fmt.Errorf("local test failed: %v", err) + } + case <-to: + return fmt.Errorf("timed out after %f seconds", timeout.Seconds()) + } + } + + return res.err +} + +func getIP(cont dockerutil.Docker) (net.IP, error) { + // The container might not have started yet, so retry a few times. + var ipStr string + to := time.After(timeout) + for ipStr == "" { + ipStr, _ = cont.FindIP() + select { + case <-to: + return net.IP{}, fmt.Errorf("timed out getting IP after %f seconds", timeout.Seconds()) + default: + time.Sleep(250 * time.Millisecond) + } + } + ip := net.ParseIP(ipStr) + if ip == nil { + return net.IP{}, fmt.Errorf("invalid IP: %q", ipStr) + } + log.Infof("Container has IP of %s", ipStr) + return ip, nil +} + +func sendIP(ip net.IP) error { + contAddr := net.TCPAddr{ + IP: ip, + Port: IPExchangePort, + } + var conn *net.TCPConn + // The container may not be listening when we first connect, so retry + // upon error. + cb := func() error { + c, err := net.DialTCP("tcp4", nil, &contAddr) + conn = c + return err + } + if err := testutil.Poll(cb, timeout); err != nil { + return fmt.Errorf("timed out waiting to send IP, most recent error: %v", err) + } + if _, err := conn.Write([]byte{0}); err != nil { + return fmt.Errorf("error writing to container: %v", err) + } + return nil +} + +func logContainer(output string, err error) { + msg := fmt.Sprintf("Container error: %v\nContainer output:\n%v", err, output) + if artifactsDir := os.Getenv("TEST_UNDECLARED_OUTPUTS_DIR"); artifactsDir != "" { + fpath := path.Join(artifactsDir, "container.log") + if file, err := os.OpenFile(fpath, os.O_WRONLY|os.O_CREATE, 0644); err != nil { + log.Warningf("Failed to open log file %q: %v", fpath, err) + } else { + defer file.Close() + if _, err := file.Write([]byte(msg)); err == nil { + return + } + log.Warningf("Failed to write to log file %s: %v", fpath, err) + } + } + + // We couldn't write to the output directory -- just log to stderr. + log.Infof(msg) +} + +func TestFilterInputDropUDP(t *testing.T) { + if err := singleTest(FilterInputDropUDP{}); err != nil { + t.Fatal(err) + } +} + +func TestFilterInputDropUDPPort(t *testing.T) { + if err := singleTest(FilterInputDropUDPPort{}); err != nil { + t.Fatal(err) + } +} + +func TestFilterInputDropDifferentUDPPort(t *testing.T) { + if err := singleTest(FilterInputDropDifferentUDPPort{}); err != nil { + t.Fatal(err) + } +} diff --git a/test/iptables/iptables_util.go b/test/iptables/iptables_util.go new file mode 100644 index 000000000..3a4d11f1a --- /dev/null +++ b/test/iptables/iptables_util.go @@ -0,0 +1,82 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package iptables + +import ( + "fmt" + "net" + "os/exec" + "time" +) + +const iptablesBinary = "iptables" + +// filterTable calls `iptables -t filter` with the given args. +func filterTable(args ...string) error { + args = append([]string{"-t", "filter"}, args...) + cmd := exec.Command(iptablesBinary, args...) + if out, err := cmd.CombinedOutput(); err != nil { + return fmt.Errorf("error running iptables with args %v\nerror: %v\noutput: %s", args, err, string(out)) + } + return nil +} + +// listenUDP listens on a UDP port and returns the value of net.Conn.Read() for +// the first read on that port. +func listenUDP(port int, timeout time.Duration) error { + localAddr := net.UDPAddr{ + Port: port, + } + conn, err := net.ListenUDP(network, &localAddr) + if err != nil { + return err + } + defer conn.Close() + conn.SetDeadline(time.Now().Add(timeout)) + _, err = conn.Read([]byte{0}) + return err +} + +// sendUDPLoop sends 1 byte UDP packets repeatedly to the IP and port specified +// over a duration. +func sendUDPLoop(ip net.IP, port int, duration time.Duration) error { + // Send packets for a few seconds. + remote := net.UDPAddr{ + IP: ip, + Port: port, + } + conn, err := net.DialUDP(network, nil, &remote) + if err != nil { + return err + } + defer conn.Close() + + to := time.After(duration) + for timedOut := false; !timedOut; { + // This may return an error (connection refused) if the remote + // hasn't started listening yet or they're dropping our + // packets. So we ignore Write errors and depend on the remote + // to report a failure if it doesn't get a packet it needs. + conn.Write([]byte{0}) + select { + case <-to: + timedOut = true + default: + time.Sleep(200 * time.Millisecond) + } + } + + return nil +} diff --git a/test/iptables/runner/BUILD b/test/iptables/runner/BUILD new file mode 100644 index 000000000..1c59e26b9 --- /dev/null +++ b/test/iptables/runner/BUILD @@ -0,0 +1,16 @@ +load("@io_bazel_rules_docker//container:container.bzl", "container_image") +load("@io_bazel_rules_docker//go:image.bzl", "go_image") + +package(licenses = ["notice"]) + +container_image( + name = "iptables-base", + base = "@iptables-test//image", +) + +go_image( + name = "runner", + srcs = ["main.go"], + base = ":iptables-base", + deps = ["//test/iptables"], +) diff --git a/test/iptables/runner/Dockerfile b/test/iptables/runner/Dockerfile new file mode 100644 index 000000000..b77db44a1 --- /dev/null +++ b/test/iptables/runner/Dockerfile @@ -0,0 +1,4 @@ +# This Dockerfile builds the image hosted at +# gcr.io/gvisor-presubmit/iptables-test. +FROM ubuntu +RUN apt update && apt install -y iptables diff --git a/test/iptables/runner/main.go b/test/iptables/runner/main.go new file mode 100644 index 000000000..3c794114e --- /dev/null +++ b/test/iptables/runner/main.go @@ -0,0 +1,70 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package main runs iptables tests from within a docker container. +package main + +import ( + "flag" + "fmt" + "log" + "net" + + "gvisor.dev/gvisor/test/iptables" +) + +var name = flag.String("name", "", "name of the test to run") + +func main() { + flag.Parse() + + // Find out which test we're running. + test, ok := iptables.Tests[*name] + if !ok { + log.Fatalf("No test found named %q", *name) + } + log.Printf("Running test %q", *name) + + // Get the IP of the local process. + ip, err := getIP() + if err != nil { + log.Fatal(err) + } + + // Run the test. + if err := test.ContainerAction(ip); err != nil { + log.Fatalf("Failed running test %q: %v", *name, err) + } +} + +// getIP listens for a connection from the local process and returns the source +// IP of that connection. +func getIP() (net.IP, error) { + localAddr := net.TCPAddr{ + Port: iptables.IPExchangePort, + } + listener, err := net.ListenTCP("tcp4", &localAddr) + if err != nil { + return net.IP{}, fmt.Errorf("failed listening for IP: %v", err) + } + defer listener.Close() + conn, err := listener.AcceptTCP() + if err != nil { + return net.IP{}, fmt.Errorf("failed accepting IP: %v", err) + } + defer conn.Close() + log.Printf("Connected to %v", conn.RemoteAddr()) + + return conn.RemoteAddr().(*net.TCPAddr).IP, nil +} |